a(n) = Product_{k = ceiling(n/2)..n-1} A090252(k).

Terms

a(0) =1a(1) =1a(2) =2a(3) =6a(4) =15a(5) =60a(6) =140a(7) =1260a(8) =2772a(9) =36036a(10) =153153a(11) =1225224a(12) =3325608a(13) =76488984a(14) =212469400a(15) =4461857400a(16) =11763078600a(17) =364655436600